Cod sursa(job #1951295)
Utilizator | Butmalai Dan ButmalaiDan | Data | 3 aprilie 2017 15:42:01 |
---|---|---|---|
Problema | Trapez | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.37 kb |
#include<bits/stdc++.h>
using namespace std;
#define d double
d x[1010],y[1010],n,rs;
unordered_map<d,int> m;
int main(){
ifstream cin("trapez.in");
ofstream cout("trapez.out");
cin>>n;
for(int i=0;i<n;i++)cin>>x[i]>>y[i];
for(int i=0;i<n;i++)for(int j=i+1;j<n;j++)m[d((x[i]-x[j])/(y[i]-y[j]))]++;
for(auto i: m){d o=i.second;rs += o*(o-1)/2;}
cout << rs;
}